1. Field of the Invention
The present invention relates to a method of cleaning the ink remaining on a photoreceptor web when an error occurs in a printer.
2. Description of the Related Art
FIG. 1 shows a conventional liquid electrophotographic printer comprising a photoreceptor web 14, a reset device 15, four optical scanning units 16, four development units 17, a drying unit 18, a transfer unit 20, and a cleaning roller 24. The reset device 15 includes an exposure device 15a for removing an electrostatic latent image by emitting light to the photoreceptor web 14, and a charger 15b for charging the photoreceptor web 14 to a predetermined level of electric potential. The optical scanning units 16 each scan information of yellow (Y), magenta (M), cyan (C) and black (K) colors to the photoreceptor web 14 circulating by a plurality of rollers 11, 12 and 13. The development units 17 provide ink of yellow (Y), magenta (M), cyan (C) and black (K) colors to the photoreceptor web 14 to develop an electrostatic latent image formed on the photoreceptor web 14 by the optical scanning units 16.
Each of the development units 17 includes an ink supply container 17f containing ink to be supplied to the photoreceptor web 14 and a development reservoir 17e where the ink dropped from the photoreceptor web 14 is collected and the collected ink can be supplied again to the ink supply container 17f. The development reservoir 17e is provided with a development roller 17a and a brush roller 17b for removing the ink adhering to the development roller 17a. In the development reservoir 17e, there is a squeegee roller 17c for separating liquid carrier, which does not contribute to image forming, of the ink supplied to the photoreceptor web 14 from the photoreceptor web 14, and a plate 17d for collecting the liquid carrier flowing down along the squeegee roller 17c to be stored in the development reservoir 17e. As shown in FIG. 2, to prevent liquid carrier from being moved toward both lateral sides of the squeegee roller 17c when the liquid carrier is separated from the photoreceptor web 14 by the squeegee roller 17c, air injectors 17g for injecting air to the photoreceptor web 14 facing the both lateral sides of the squeegee roller 17c are provided.
The drying unit 18 is for absorbing and vaporizing the liquid carrier remaining on the photoreceptor web 14. The transfer unit 20 includes a transfer roller 21 and a fusing roller 22 for transferring a toner image formed on the photoreceptor web 14 to a sheet of paper 23 being supplied.
When an error such as paper jam occurs while the paper 23 is supplied to the transfer unit 20 from a paper supply portion (not shown) during a printing operation, a controller (not shown) for controlling the printer interrupts the printing operation until the error is removed. When the printing operation is stopped due to such an error, the ink supplied to the photoreceptor web 14 is hardened and the photoreceptor web 14 is polluted. Thus, after the error is removed, the remaining ink should first be removed before the printing continues.
Previously, to remove the ink remaining on the photoreceptor web 14, the photoreceptor web 14 is rotated several times in a state in which the cleaning roller 24 is in contact with the transfer roller 21 contacting the photoreceptor web 14. However, as the surface of the transfer roller 21 is continuously cleaned by the cleaning roller 24, a transfer rate of ink from the photoreceptor web 14 to the transfer roller 21 is lowered when a large amount of ink remains on the surface of the transfer roller 21. As a result, the photoreceptor web 14 must be rotated several times to clean the photoreceptor web 14 within an acceptable amount of remaining ink so that the cleaning work takes much time.